Garbage collection in JDBC

I am doing a JProbe testing on a use-case. Inspite of closing all open resources (resultset and PreparedJDBCStatement) , the snapshot(Jprobe) reports instances of OracleStatement on the heap. The memory of this is considerably high . I wish to know why these instances were not garbage collected by the JVM. The application uses Oracle type 4 driver.

The instance view detail lists a number of T4CNumberAccessorXXXXXXX(rowSpaceChar). What is this?

I think your issues might fall under the category of general garbage collection such as is there still a reference to these objects anywhere in the system, have you tried calling System.gc() after making large calls, and are trying to load more data into memory than available.